Harbour Extension.

Taranaki Herald, Volume XLIX, Issue 11818, 15 November 1901, Page 2

Harbour Extension.

MR NAPIER BELLS REPOTiT.

The following is Mr JNapior Moll's report to the Harbour Board on Uie . subject of increased accominodatl"i» lor shipping and the extension ,q£. shelter necessary to be provided'^or' ii*e same': — 1 will first take.,,i}Ro consideration the often propoijeri pioject of making a breakwarci* uom Mikotahi i-'oint to Moturoa island and from that island starting a breakwater to enclose a deif. watei harbour.

Mr James Half our in 1866 and Mr John Garruthers j.in 1879 rorfotf.^3 on this subject, and no new .litfhi that I know of has bet?n thrown on it. To make ,such a harbour it would be necessary to niake "a breakwater of the strongest description, from Miko.tahi Point to Moturoa Js r land, as a very heavy sea drives through this strait; the distance i& 1130 feet anjd the cost would be ab^ out £60,000. Then the real shelter foi such a pprt would be effected, by a breakwater in an easterly direction from Moturoa Island, but this must be built in depths of 42 feet of water at low water. .To ,b,uiUt this breakwater" of" rubble, wotthi cost about £98 per running foct but 1 doubt whether sufficient stone of suitable" sifce i&" to be had in *W« neighbourhood. If the -stone—is uc oi suitable size then it mlist be built of concrete blocks on a a rubble mound, the top of ,whisi7vvq&l£lllte 15 feet or so undW s -lcfw^watefVivlll» wave^br-eakers'.. of rubble blocks on the "outside, and this structure would cost about £125 per running foot.

But apart from the ,■ cosl(O^the) breakwater, the site- has many in-, conveniences; the bottom where the wharves would be is said to be alii rock, and to get at these wharves, the railway would have to cross, over on the breakwater between ML-; kotohi and Moturoa Island, the ob-,< jQctfari Ith which is: t .that, , in a f h^avJ^ sea.i tiiePspray w'c»uld'fr^t wildly^^-j the train. The only advantage thi^ position has over the 'present, sitejjs that no " dredging would have" tb'-itoi done to admit the. very largest vessels to the. .wharvps, bufr.K dredgingis done oti "the- present 1 site then, it is better and more convenient' than} the site of Moturoa Island, and 1^ have no doubt that the..cheaper-,co!3t; of a bpeakwatfer-,ph't]khe^ r «^^iy s H l e' woi'.'i more than pay for the dredg-; ing, ,to admit th.c largest' vessels ' . , . '•« ' .v '" - In any case" the time" has passed when the Moturoxi site could be seriously considered. At present tM« consideration in to extend the exist-i ing breakwater to something .like; iiheUen^thjbtiginall^ ddftttheffi J . •? Wrutn'er^,T TdlMki S Srould/iiUfce: gjven a splendid harbour with abun dance qf. water. .But v«ie;lact jOfcAh* di if ting of sand . roiind the t)reak-i water must modify 1 one's idet>.a as to! the* capacity, pt the harbour; be^ cause, - arlthough " • tne oreakwater;^ might be made to enclose any qUan^ tity of deep water, yet the fand in time will nil all up, xvftichtis^tfot kept deep by dredging. <Bi thiß' ires-r pect the -jMoturoa site would not offer any' advantage, because, if the breakwaters had been made there originally, 1 have little ■■' doubt^ that by this time ,the sand would have found its way round the end and in ; to the harbour, and therefore dredgr ing would have Had to be doneeveil at the Moturoa site. The question of sites for this port has been carefully considered by-Sii John Coode, Mr John Carruthers, and Mr Blackett, and after studying thd chart of soundings made by Mi Edgar C Jones, one can see that the site of the prjsent breakwater is noi ill-chosen. It is true, t^at the water is somewhat shallow close inshore, but the offing all round and well .into the land towards the East is-veYj deep; ; consequently the, approach il safe and easy to navigate both out ,an.d in. It is very creditable to^hjb harbour officers that they have managed so well wifch the 'break.watej 1 •short as it is, so that in the Ve&*\ •enly four • -vessels have had +0 pasa by through stress of weath.jf Bu' no pn-. doubts that the breakwater is {or. too short for efficient shelten, and consequently considerable >darj- ' age is incurred >o ship^s, Io «jiewharf and to , the tackle used, n,ot iV mentiop. theiisk of being canqtiv m suoh a narrow place in a, gs'e «|< wintl. AU such .disadvantages would, bis quite abated il. the breakwater were lengthened/ io ■which case vessels berthed en, this port would fedr no weather. , ' " „ f\ : Aftc-' carefully 1 'considering ..Air Mar'chant's project for. extension >V. tho bieakwater, I come to the' craclusioh that ihe extent to wufch }}«.- propose", to lengthen it is' about a* much as jp admissable in View c. 1 .i.-jc / dredging that .will be requir vi. art, \6 my 'mind enough for the trad^ y" the district jtrdw, of Sn *het-jtur»j. jJ have agreed 'witK him' tha.t \i in nft t admissable, at present to make .tne east wall as ihown A in -hisr )»laA. y H\^ though It can bo undertaken in the. future when,' as he shows) it; would . affor'i good sites for additional ship-, ping berthage. At present it would serve, a better purpose il some of tfie cost of it were taken to 'still furtlhfer lengthen 'the ' breakwater • whiclwould therefore be, extended 1000* feet. This would give a very gos>e-' shelter to the present wharf when: fi&so ''extended, and'also -to an aSdi-v tional Wharf, . which, is shown . on, the' •pla*h tp b 6 erected in -tho J future: wfieti required and referred 'to at me.' en^'V>f t^iifc l'eiort. : " \ '; ; V > 1 would 're'eommend the breakwater to fee , tfujlt "of rubble stone capped with corliCrete blpcks, that is, provided sufficient f oek is ,to be had. lit "seems dbubtful, if.' there i - r sl|fficiflftt rock in "tho present quarrie. 1:,5l :,5 antl^f not tlieh the Paritiitu Hill must (Mr quarrjed. The original intention. ] Oft Sir J .. Coode arid Mr Carruthers was* tou se' this' Hilt as a quarry ." Those who have examined .the stone "do not think much of its appearance, but it should be prospected to see if good sound sjt'one is to be had. < , When the" breakwater is lengthened, the present wharf is- to be exte^d,od^4,oo feet by a width of -5,0 feet, which, permits of the berthage of ;tw6 of the jiapgest steamers,, one leaves the v exjsting wharf for the usf ' of' snxalJi.Qr ves^eljsL c fiie' dredging °as defined by Mi Maichant its quijLe t swijbable, and th( only question is as to the cost of it. 'as from want of borings one cannot tell how much is sand and how much soft sandstone. It shows a area Under shelter of tha breakwater to be dredged to 25 feet below low water with one berth on the insid< of the wharf extension dredged' to 3ft feef. r v qJHjt©* v ag/ee that it is goojd policy to dredge foahpr.p jnsteadt 9 extending the breakwater bo asi.tr avoid dredging, as it is in this case far cheaper to dredge than to extend the works into deeper water. Much of this area shown to be dredged if liable to be more or less silted uj by drift sand coming round the entf of 1me l 'breakiYater, but when oncf. tho dredgiftg'-'^ 'flonb jlo ths depthV shown, the quantity coming rounc' is not In6'rea c sod" thereby, and the depth of the port will then be maintained by the yearly amount pf dredging required to keep down tht drift, whatever the amount may be. I agree With Mr Marchant that to dredge cli'e&pjy and with dispatch the port stfould pcissesjs' iji good sand pump dredge witp'a' hopper capacity ot abput '250 Jbons."" Mr Marchanr thinks ijb miisjt be mounited with 0 buckejt fodder to 'dredge hard mater^' ial, and' i/ .there w puch hard roatr crial no ffQ.ubt jh&t *P necesßary, but 1 \h<«k^r/pgb shqfltf be taken over the are* tq p$ dredged before purchasing a dredge, yvfien dnco-the entire dredging is done to the depths proposed, then nothing but tho sand pump will be needed tb maintain £fr£ 4SPth» and this can be done at a vtery^derat* yearly cost if tho quantity np mbrp than 70, 000 cubits yarcls &. y^ay. ~ In flmki^g dfisfcr^s for extension of the shipping afi/s^inmodation, it has occurred (to vnfi thai were as well to sea wfta^ ppoyisipn coufd bp made for - the utmPSt accommodation which the propbsed e^tftnfiipn 'of the breakwater would admit of, even although it is not contemplated at present. With this view I have indicated on plan herewith an additional wharf for. large steamers with a wharf inside of it for smaller vessels, thts laftw being protected by a rubble bank which forms the approach to the deep water wharf. The lines of rail giving access to: these wharves would be placed oni reclaimed land as Rhqwn on ilan.j The breakwater' extension proposed* would, therefore give shelter to wbftrvo* wiw» a toUl berthase

length of 3170 feet, that is, for about nine vessels, four >of which would be of the largest size, and New Plymouth would be very prosperous indeed if it could find trade for all this shipping. : The * following is an approximate' estimate of the proposed works, -not including the additional wharves and .reclaimed land mentioned in "the last r •paragraph : — Breakwater extension'1060 feet at £75— £70,875 Inclined approach in concrete — £1500. Wharf extension £10,800. Dredging say,— £l7,ooo. New dredge— £l6, 000. Moorings £1500. Extra plant £3500— £130,175. Contingencies, 10 pcr 1 cent., £13017. Totals £143, 192.